In a recent mobile wireless apparatus such as a mobile phone, since it is necessary to meet requirements for miniaturization as well as multifunctionality and high performance, a structure in which two housings are openably connected to each other is mainly employed. For connection between the two housings, a scheme such as a folding type, a folding type (may be referred to as a double swivel type) including a two-axis hinge, and a slide type has been extensively used. Among them, the slide type is characterized in that an opening and closing operation is simple and a display screen is easily visible although the two housings are closed.
Any one of the two housings slidably engaged with each other has an antenna therein. A part of each housing may be made of a conductive material such as a metal. Each housing has a conductor section such as a ground pattern of a circuit board. Since a positional relationship between the antenna and these housings or the conductor section of the circuit varies depending on the opening and closing of the slide structure, which may affect antenna characteristics.
JP-A-2008-5207 discloses a technology that aims at maintaining good antenna characteristics in the state in which two housings of a slide type mobile wireless apparatus (a slide type mobile terminal) are opened or closed with respect to each other.
The slide type mobile terminal disclosed in JP-A-2008-5207 includes a first housing provided with a conductor member, a second housing provided with an embedded antenna and a power feed circuit, a slide means that slidably connects the first housing to the second housing, and a conductive coupling member which is connected to the conductor member so as to simultaneously slide together with the conductor member and is connected to the embedded antenna and the power feed circuit in the open state of the slide structure.
In the slide type mobile terminal disclosed in JP-A-2008-5207, the embedded antenna and the conductor member of the first housing are connected in parallel to the power feed circuit of the second housing in the open state of the slide structure. As a result, a ground circuit (a ground member included in the second housing) for the power feed circuit and the conductor member of the first housing form a dipole antenna, and are excited together with the embedded antenna (a modified example in which power supplied to the embedded antenna is interrupted in the open state is also disclosed therein). Meanwhile, in a closed state of the slide structure, only the embedded antenna is excited. In addition, JP-A-2008-5207 also discloses a configuration in which an opening and closing detector and two matching circuits are provided, and the two matching circuits are switched to meet antenna matching conditions in the open state and the closed state.
According to the slide type mobile terminal disclosed in JP-A-2008-5207, in the open state of the slide structure, since the conductor member of the first housing is connected to the power feed circuit of the second housing through the conductive coupling member, the dipole antenna formed over the first housing and the second housing is excited. Meanwhile, in the closed state of the slide structure, only the embedded antenna is excited.
The slide type mobile terminal disclosed in JP-A-2008-5207 requires switching of the matching circuits or switching of embedded antenna connection according to a change of the circuit configuration caused by the opening and closing of the slide structure, separately from switching of the connection through the conductive coupling member. That is, the circuit configuration may be complicated and the housings may not be fabricated at a small size.